Source : Webster's Revised Unabridged Dictionary (1913)

Lateral \Lat"er*al\, a. [L. lateralis, fr. latus, lateris, side:
   cf. F. lat['e]ral.]
   1. Of or pertaining to the sides; as, the lateral walls of a
      house; the lateral branches of a tree.

   2. (Anat.) Lying at, or extending toward, the side; away from
      the mesial plane; external; -- opposed to {mesial}.

   3. Directed to the side; as, a lateral view of a thing.

   {Lateral cleavage} (Crystallog.), cleavage parallel to the
      lateral planes.

   {Lateral equation} (Math.), an equation of the first degree.
      [Obs.]

   {Lateral line} (Anat.), in fishes, a line of sensory organs
      along either side of the body, often marked by a distinct
      line of color.

   {Lateral pressure} or {stress} (Mech.), a pressure or stress
      at right angles to the length, as of a beam or bridge; --
      distinguished from longitudinal pressure or stress.

   {Lateral strength} (Mech.), strength which resists a tendency
      to fracture arising from lateral pressure.

   {Lateral system} (Bridge Building), the system of horizontal
      braces (as between two vertical trusses) by which lateral
      stiffness is secured.

Source : WordNet®

lateral line
     n : sense organs of fish and amphibians; believed to detect
         pressure changes in the water [syn: {lateral line organ}]